A hollow artificial log is formed by creating a mat or blanket of a mineral fiber and a binder is formed with a desired surface appearance. The mat or blanket may be used as formed or to make a log, further processed by forming the mat around a core so that it is at least a partial tube open at both ends, and it is then oven cured. A gas burner tube may be placed within the partial enclosure formed by the partial tubular log wall to simulate a real log burning.
In the prior art, various compositions and methods for making artificial logs for gas fireplace have been advanced, including vacuum forming of logs. However, the logs are generally solid and become quite heavy. An additional problem with the use of artificial logs has been that the gas burners used are difficult to hide and this results in the gas fireplace not having a true "natural" look.
In my copending application Ser. No. 08/569,483, filed Dec. 5, 1995, now U.S. Pat. No. 5,800,875, a method of forming solid logs is disclosed. The materials used are the same that are used with the present invention. Fiber logs such as that shown in my copending application are light weight. They also glow when flames impinge on the surface, and they look very realistic. The solid logs formed use a high volume of slurry containing water and thus require substantial drying time, and extra material. The production costs are increased because of the drying requirements.
Artificial logs were first made with refractory cement. The forming process was simple, and the logs looked reasonably natural, but they were very heavy, approximately ten times the weight of the present mineral fiber logs. Refractory cement logs would also become coated with carbon where the flame impinged on the log surface.
U.S. Pat. No. 3,377,229 shows a ceramic log that defines an open interior space. The ceramic log in patent '229 has a bottom support wall and a side wall which curves up and over the bottom support wall to simulate a log surface. The log is provided with end walls that define a cavity. The outer wall is formed in layers.